Polymer-baking types of graphite films have excellent heat-dissipating properties, and as such, are used as heat dissipation components for dissipating heat from components that generate heat, e.g., for semiconductor elements that are mounted in various electronic or electric apparatuses such as computers. A conventional method for producing a graphite film has included a carbonization step for pre-baking a polymer film at temperatures up to approximately 1000° C. and a graphitization step for heat-treating, at temperatures up to approximately 2700° C., the carbonized film given by the carbonization step. For example, Patent Literature 1 discloses a method for producing a thick graphite film by using a 125-μm polyimide film as a raw material. Patent Literature 1 discloses that a graphite film having an even, flat surface is produced by performing carbonization at temperatures up to 1000° C. at a heating rate of 5° C./min and performing graphitization at temperatures up to 2800° C. at a heating rate of 1° C./min.
Incidentally, Patent Literature 2 discloses a method for producing a graphite film by using a 75-μm polyimide film as a raw material. Patent Literature 2 discloses that a graphite film is produced by performing carbonization at temperatures up to 1600° C. at a heating rate of 1° C./min, 5° C./min, or 20° C./min and performing graphitization at temperatures up to 2700° C. at a heating rate of 3° C./min.